Pontiac 400 V8 Engine
The Pontiac 400 6.6 Liter engine was first introduced in 1967. This version of the Pontiac V8 engine was used in the GTO, Firebird, and the Trans-Am Firebird.
The 400 was inspired by the Pontiac 389 V8 and proved to be the last Pontiac engine with closed chambered heads. At the start of the 1970s, the 400 V8 generated more than 300 horsepower, but decreased to 180 horsepower by the time the last 400 engine was produced in 1978. The special edition black and gold Trans Am made famous by Burt Reynolds in the Smokey and the Bandit movie franchise increased Firebird sales in 1977 and 1978 and made the 400 V8 quite popular. Even though production of the 400 had ceased, 1979 Pontiac models still featured the 400 engine due to large stockpiles left over from the previous year.
In 1980, Pontiac decided to use the Pontiac 301, 4.9 V8 engine to replace the 400. Sales and the new engine’s performance failed miserably and the 301 was no longer offered by Pontiac after 1981.
Engine Specifications
1967-1970 with 4-Barrel Carb
Max Brake Horsepower: 330@ 4800rpmMax Torque: 430 @ 3000 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 10.5
Firing Order: 18436572
1967-1970 High Output with 4-Barrel Carb
Max Brake Horsepower: 335@ 5000rpmMax Torque: 430 @ 3400 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 10.5
Firing Order: 18436572
1967-1970 Ram Air III with 4-Barrel Carb
Max Brake Horsepower: 345@ 5000rpmMax Torque: 430 @ 3400 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.0
Firing Order: 18436572
1967-1970 Ram Air IV with 4-Barrel Carb
Max Brake Horsepower: 370@ 5500rpmMax Torque: 445 @ 3900 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.0
Firing Order: 18436572
1971 with 4-Barrel Carb
Max Brake Horsepower: 300@ 4800rpmMax Torque: 400 @ 3600 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.0
Firing Order: 18436572
1972 with 4-Barrel Carb
Max Brake Horsepower: 250@ 4400rpmMax Torque: 325 @ 3200 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.0
Firing Order: 18436572
1973 with 4-Barrel Carb
Max Brake Horsepower: 230@ 4400rpmMax Torque: 325 @ 3200 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.0
Firing Order: 18436572
1974 with 4-Barrel Carb
Max Brake Horsepower: 225@ 4000 rpmMax Torque: 330 @ 2800 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.0
Firing Order: 18436572
1975 with 4-Barrel Carb
Max Brake Horsepower: 185@ 3600rpmMax Torque: 310 @ 1600 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 7.6
Firing Order: 18436572
1976 with 4-Barrel Carb
Max Brake Horsepower: 185@ 3600rpmMax Torque: 310 @ 1600 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 7.6
Firing Order: 18436572
1977 with 4-Barrel Carb
Max Brake Horsepower: 180@ 3600rpmMax Torque: 325 @ 1600 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 8.1
Firing Order: 18436572
1978 with 4-Barrel Carb
Max Brake Horsepower: 180@ 3600rpmMax Torque: 325 @ 1600 rpm
Stroke: 3.75
Bore: 4.1212
Compression: 7.6
Firing Order: 18436572